As one of the world's three major food crops and an important economic and oil crop,soybean plays a crucial role in ensuring food safety.In recent years,there are many problems in soybean cultivation,production an...As one of the world's three major food crops and an important economic and oil crop,soybean plays a crucial role in ensuring food safety.In recent years,there are many problems in soybean cultivation,production and processing.In view of this situation,this paper comprehensively expounded and decomposed the cultivation situation,existing problems,specific countermeasures and conclusions,so as to re-recognize them.This study provides reference materials for the sustainable and healthy development of the soybean industry.展开更多
With the development of technology,diffusion model-based solvers have shown significant promise in solving Combinatorial Optimization(CO)problems,particularly in tackling Non-deterministic Polynomial-time hard(NP-hard...With the development of technology,diffusion model-based solvers have shown significant promise in solving Combinatorial Optimization(CO)problems,particularly in tackling Non-deterministic Polynomial-time hard(NP-hard)problems such as the Traveling Salesman Problem(TSP).However,existing diffusion model-based solvers typically employ a fixed,uniform noise schedule(e.g.,linear or cosine annealing)across all training instances,failing to fully account for the unique characteristics of each problem instance.To address this challenge,we present GraphGuided Diffusion Solvers(GGDS),an enhanced method for improving graph-based diffusion models.GGDS leverages Graph Neural Networks(GNNs)to capture graph structural information embedded in node coordinates and adjacency matrices,dynamically adjusting the noise levels in the diffusion model.This study investigates the TSP by examining two distinct time-step noise generation strategies:cosine annealing and a Neural Network(NN)-based approach.We evaluate their performance across different problem scales,particularly after integrating graph structural information.Experimental results indicate that GGDS outperforms previous methods with average performance improvements of 18.7%,6.3%,and 88.7%on TSP-500,TSP-100,and TSP-50,respectively.Specifically,GGDS demonstrates superior performance on TSP-500 and TSP-50,while its performance on TSP-100 is either comparable to or slightly better than that of previous methods,depending on the chosen noise schedule and decoding strategy.展开更多
This study examines the mediating role of positive psychological capital and the moderating role of ethnicity in the relationship between mindfulness and internalizing/externalizing problems among adolescents.The stud...This study examines the mediating role of positive psychological capital and the moderating role of ethnicity in the relationship between mindfulness and internalizing/externalizing problems among adolescents.The study sample comprized Chinese adolescents(N=637 ethnic minority;females=40.97%,meam age=12.68,SD=0.49 years;N=636 Han;females=49.06%,mean age=12.71,SD=0.47 years).The participants completed the Child and Adolescent Mindfulness Measure,the Positive Psycap Questionnaire,and the Youth Self-Report.Results from the moderated mediation analysis showed mindfulness was negatively associated with both internalizing and externalizing problems.Ethnicity moderated the relationship between mindfulness and internalizing problems to be stronger for Han adolescents compared to ethnic minority adolescents.Psychological capital mediated the relationship between mindfulness and internalizing problems in both groups,with a negative direction.Findings support the Conservation of Resources theory and highlight mindfulness as a personal resource fostering adolescent well-being in multicultural contexts.展开更多
Generalised reduced masses with a set of equations governing the three relative motions between two of 3-bodies in their gravitational field are established,of which the dynamic characteristics of 3-body dynamics,fund...Generalised reduced masses with a set of equations governing the three relative motions between two of 3-bodies in their gravitational field are established,of which the dynamic characteristics of 3-body dynamics,fundamental bases of this paper,are revealed.Based on these findings,an equivalent system is developed,which is a 2-body system with its total mass,constant angular momentum,kinetic and potential energies same as the total ones of three relative motions,so that it can be solved using the well-known theory of the 2-body system.From the solution of an equivalent system with the revealed characteristics of three relative motions,the general theoretical solutions of the 3-body system are obtained in the curve-integration forms along the orbits in the imaged radial motion space.The possible periodical orbits with generalised Kepler’s law are presented.Following the description and mathematical demonstrations of the proposed methods,the examples including Euler’s/Lagrange’s problems,and a reported numerical one are solved to validate the proposed methods.The methods derived from the 3-body system are extended to N-body problems.展开更多
The proliferation of carrier aircraft and the integration of unmanned aerial vehicles(UAVs)on aircraft carriers present new challenges to the automation of launch and recovery operations.This paper investigates a coll...The proliferation of carrier aircraft and the integration of unmanned aerial vehicles(UAVs)on aircraft carriers present new challenges to the automation of launch and recovery operations.This paper investigates a collaborative scheduling problem inherent to the operational processes of carrier aircraft,where launch and recovery tasks are conducted concurrently on the flight deck.The objective is to minimize the cumulative weighted waiting time in the air for recovering aircraft and the cumulative weighted delay time for launching aircraft.To tackle this challenge,a multiple population self-adaptive differential evolution(MPSADE)algorithm is proposed.This method features a self-adaptive parameter updating mechanism that is contingent upon population diversity,an asynchronous updating scheme,an individual migration operator,and a global crossover mechanism.Additionally,comprehensive experiments are conducted to validate the effectiveness of the proposed model and algorithm.Ultimately,a comparative analysis with existing operation modes confirms the enhanced efficiency of the collaborative operation mode.展开更多
Convex feasibility problems are widely used in image reconstruction, sparse signal recovery, and other areas. This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recov...Convex feasibility problems are widely used in image reconstruction, sparse signal recovery, and other areas. This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery. We first derive the projection formulas for a vector onto the feasible sets. The centralized circumcentered-reflection method is designed to solve the convex feasibility problem. Some numerical experiments demonstrate the feasibility and effectiveness of the proposed algorithm, showing superior performance compared to conventional alternating projection methods.展开更多
During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive...During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive distance)to a moving target as quickly as possible,resulting in the extended minimum-time intercept problem(EMTIP).Existing research has primarily focused on the zero-distance intercept problem,MTIP,establishing the necessary or sufficient conditions for MTIP optimality,and utilizing analytic algorithms,such as root-finding algorithms,to calculate the optimal solutions.However,these approaches depend heavily on the properties of the analytic algorithm,making them inapplicable when problem settings change,such as in the case of a positive effective range or complicated target motions outside uniform rectilinear motion.In this study,an approach employing a high-accuracy and quality-guaranteed mixed-integer piecewise-linear program(QG-PWL)is proposed for the EMTIP.This program can accommodate different effective interception ranges and complicated target motions(variable velocity or complicated trajectories).The high accuracy and quality guarantees of QG-PWL originate from elegant strategies such as piecewise linearization and other developed operation strategies.The approximate error in the intercept path length is proved to be bounded to h^(2)/(4√2),where h is the piecewise length.展开更多
Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when ta...Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems.展开更多
The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet ...The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet dynamics,are demonstrated in the current research.Hereby,the 2nd Stokes problem assumes that the surface,with a thin shared layer of the fluid on it,oscillates in a harmonic manner along the x-axis of the rivulet flow,which coincides with the main flow direction streaming down the underlying surface.We obtain the exact extension of the rivulet flow family,clarifying the structure of the pressure field,which fully absorbs the arising perturbation.The profile of the velocity field is assumed to be Gaussian-type with a non-zero level of plasticity.Hence,the absolutely non-Newtonian case of the viscoplastic flow solution,which satisfies the motion and continuity equations,is considered(with particular cases of exact solutions for pressure).The perturbed governing equations of motion for rivulet flows then result in the Riccati-type ordinary differential equation(ODE),describing the dynamics of the coordinate x(t).The approximated schematic dynamics are presented in graphical plots.展开更多
This study proposes a class of augmented subspace schemes for the weak Galerkin(WG)finite element method used to solve eigenvalue problems.The augmented subspace is built with the conforming linear finite element spac...This study proposes a class of augmented subspace schemes for the weak Galerkin(WG)finite element method used to solve eigenvalue problems.The augmented subspace is built with the conforming linear finite element space defined on the coarse mesh and the eigen-function approximations in the WG finite element space defined on the fine mesh.Based on this augmented subspace,solving the eigenvalue problem in the fine WG finite element space can be reduced to the solution of the linear boundary value problem in the same WG finite element space and a low dimensional eigenvalue problem in the augmented sub-space.The proposed augmented subspace techniques have the second order convergence rate with respect to the coarse mesh size,as demonstrated by the accompanying error esti-mates.Finally,a few numerical examples are provided to validate the proposed numerical techniques.展开更多
Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update....Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update. In the research, opti-mization ways of tobacco barn were analyzed in flue-cured tobacco production re-gions, and assessment was made on improvement effects, in order to provide refer-ences for highly-efficient and low-carbon development of curing barn.展开更多
China is a large agricultural country. Healthy and rapid development of agriculture plays an important role in overall socialist construction of China. To realize sustainable agricultural development,cultivation of ag...China is a large agricultural country. Healthy and rapid development of agriculture plays an important role in overall socialist construction of China. To realize sustainable agricultural development,cultivation of agricultural science and technology innovation talents should be strengthened. Through analyzing existing problems in cultivation of agricultural science and technology innovation talents and combining actual situation of China's agricultural development,this paper came up with pertinent recommendations for strengthening China's agricultural science and technology talent cultivation,including improving agricultural science and technology innovation talent cultivation system,implementing " government- industry- university- institute" talent cultivation mode,speeding up construction of experimental teaching demonstration center,and applying human resource theories.展开更多
In 2012,China's total grain yield reached 590 million tons and realized nine consecutive years of growth. This is huge historic achievement of China and also rare in development history of world agriculture. Howev...In 2012,China's total grain yield reached 590 million tons and realized nine consecutive years of growth. This is huge historic achievement of China and also rare in development history of world agriculture. However,at the same time of making great achievements,China's agriculture is still confronted with many problems. On the basis of extensive survey,it pointed out 10 outstanding problems: farmland,labor,livestock power,water conservancy,input,agricultural disaster,ecological and environmental problem,waste of resources,economic scale and economic benefits. These problems have brought great adverse influence on China's agricultural development. In view of these problems,to realize sustainable,stable and healthy development of agriculture in the new period,it came up with following recommendations:( i)deepening the understanding;( ii) enforcing laws strictly;( iii) enhancing training;( iv) increasing benefits;( v) saving resources;( vi) protecting environment;( vii) developing science and technology;( viii) consolidating foundation.展开更多
Since the seventies,world economy has been engaged in adjustment princi-pally in the following three fields.First,the shift of economic developmentmode from that of aggregate quantitative growth to that of quality-eff...Since the seventies,world economy has been engaged in adjustment princi-pally in the following three fields.First,the shift of economic developmentmode from that of aggregate quantitative growth to that of quality-effective-ness.Second,the reform of economic system with more and more countries realiz-ing market economy.Third,the economy getting more opened as economic global-ization further avdances.展开更多
The cultivation of the economic crop flue-cured tobacco is greatly impacted by natural climates,making it a risk industry.In recent years,flue-cured tobacco production is influenced by extreme weather such as typhoon,...The cultivation of the economic crop flue-cured tobacco is greatly impacted by natural climates,making it a risk industry.In recent years,flue-cured tobacco production is influenced by extreme weather such as typhoon,low temperature,hail,frost,drought,plant diseases and insect pests.It is imperative to establish a sound insurance system for tobacco planting.In this paper,the practice and functions of tobacco planting insurance in Qianxinan Prefecture were summarized,the experience and existing problems in the practice process were analyzed,and finally the countermeasures and suggestions were proposed to further improve the tobacco planting insurance.展开更多
China takes the road of tourism development,and the tourism industry is gradually branded,which is also a reflect of tourism management to adapt to the trend of the times.Tourism is an important economic project for t...China takes the road of tourism development,and the tourism industry is gradually branded,which is also a reflect of tourism management to adapt to the trend of the times.Tourism is an important economic project for the participation of the whole people.By optimizing the local resources,the tourism space is carried out in an orderly manner,and the rich tourism products are displayed in front of the tourists.With the development of tourism,the scientific tourism system has been established,and the globalization of tourism has been realized.To promote the healthy development of tourism,tourist signs are essential.From the current established tourism signage system,there are still some problems,which affect the quality of tourism management.It is necessary to take corresponding countermeasures.This paper focuses on the causes and strategies in response to the existing problems in the tourism signage system.展开更多
The development of rural industries in Bijie City of Guizhou Province leads the comprehensive rural revitalization with industrial revitalization,takes high-quality development as the overall guide,focuses on industri...The development of rural industries in Bijie City of Guizhou Province leads the comprehensive rural revitalization with industrial revitalization,takes high-quality development as the overall guide,focuses on industrial scale,standardization,branding,and marketization,and strives to extend the industrial chain and enhance the value chain to achieve the prosperity of rural industries.In this study,it investigated the current situation of rural industry development in Bijie City(improving the quality and efficiency of characteristic industries,expanding the quantity and efficiency of agricultural products processing industry,recruiting and cultivating large business entities,expanding and strengthening the brand of agricultural products,and upgrading the rural tourism).Through analysis,it found that there are problems such as small scale of production enterprises,insufficient cultivation of independent brands,short industrial chain,low added value,weak market expansion ability,imperfect interest connection mechanism,and insufficient participation of farmers.Finally,it came up with countermeasures for the development of rural industries in Bijie City,including improving supporting facilities and building an extension base;strengthening leading enterprises and focus on deep processing;highlighting regional characteristics and paying close attention to the docking of production and marketing;enhancing the characteristic brand and strengthening the support of science and technology;promoting collaboration and support,and making innovation in the connection of interests.展开更多
In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are d...In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are discussed.The research aims to provide reference for the management of the Longgang River basin.展开更多
Performance management is one of the important contents of enterprise operation management. The effectiveness of performance management will directly affect the overall performance of the enterprise, so the developmen...Performance management is one of the important contents of enterprise operation management. The effectiveness of performance management will directly affect the overall performance of the enterprise, so the development of performance management is of great significance. But from the current situation, there are still some deficiencies in the performance management of many enterprises, leading to the actual role of performance management can not be played. Therefore, we should analyze and optimize the existing problems of enterprise performance management system.展开更多
At present, China's social and economic development is accelerating, and the quality and overall level of municipal road projects have been greatly improved. However, with the prosperity of traffic, road traffic c...At present, China's social and economic development is accelerating, and the quality and overall level of municipal road projects have been greatly improved. However, with the prosperity of traffic, road traffic congestion and road aging problems have become increasingly prominent. The renovation project of old municipal roads has gradually become the focus of attention. The transformation of municipal roads is imminent. Therefore, we must strictly control the construction quality of the old road renovation project municipal roads, ensure the control and measurement of the old road renovation project municipal roads, and then improve the overall environmental level of the city, increase the residents' sense of belonging, and promote the rapid development of the urbanization process .展开更多
基金Supported by Special Fund for National Modern Agricultural Industry Technology System Construction(CARS-04-CES16).
文摘As one of the world's three major food crops and an important economic and oil crop,soybean plays a crucial role in ensuring food safety.In recent years,there are many problems in soybean cultivation,production and processing.In view of this situation,this paper comprehensively expounded and decomposed the cultivation situation,existing problems,specific countermeasures and conclusions,so as to re-recognize them.This study provides reference materials for the sustainable and healthy development of the soybean industry.
基金supported by the National Science and Technology Council,Taiwan,under grant no.NSTC 114-2221-E-197-005-MY3.
文摘With the development of technology,diffusion model-based solvers have shown significant promise in solving Combinatorial Optimization(CO)problems,particularly in tackling Non-deterministic Polynomial-time hard(NP-hard)problems such as the Traveling Salesman Problem(TSP).However,existing diffusion model-based solvers typically employ a fixed,uniform noise schedule(e.g.,linear or cosine annealing)across all training instances,failing to fully account for the unique characteristics of each problem instance.To address this challenge,we present GraphGuided Diffusion Solvers(GGDS),an enhanced method for improving graph-based diffusion models.GGDS leverages Graph Neural Networks(GNNs)to capture graph structural information embedded in node coordinates and adjacency matrices,dynamically adjusting the noise levels in the diffusion model.This study investigates the TSP by examining two distinct time-step noise generation strategies:cosine annealing and a Neural Network(NN)-based approach.We evaluate their performance across different problem scales,particularly after integrating graph structural information.Experimental results indicate that GGDS outperforms previous methods with average performance improvements of 18.7%,6.3%,and 88.7%on TSP-500,TSP-100,and TSP-50,respectively.Specifically,GGDS demonstrates superior performance on TSP-500 and TSP-50,while its performance on TSP-100 is either comparable to or slightly better than that of previous methods,depending on the chosen noise schedule and decoding strategy.
基金supported by the Guizhou Provincial Science and Technology Projects[Basic Science of Guizhou-[2024]Youth 309,Guizhou Platform Talents[2021]1350-046]Zunyi Science and Technology Cooperation[HZ(2024)311]+3 种基金Funding of the Chinese Academy of Social Sciences(2024SYZH005)Peking University Longitudinal Scientific Research Technical Service Project(G-252)Guizhou Provincial Graduate Student Research Fund Project(2024YJSKYJJ339)Zunyi Medical University Graduate Research Fund Project(ZYK206).
文摘This study examines the mediating role of positive psychological capital and the moderating role of ethnicity in the relationship between mindfulness and internalizing/externalizing problems among adolescents.The study sample comprized Chinese adolescents(N=637 ethnic minority;females=40.97%,meam age=12.68,SD=0.49 years;N=636 Han;females=49.06%,mean age=12.71,SD=0.47 years).The participants completed the Child and Adolescent Mindfulness Measure,the Positive Psycap Questionnaire,and the Youth Self-Report.Results from the moderated mediation analysis showed mindfulness was negatively associated with both internalizing and externalizing problems.Ethnicity moderated the relationship between mindfulness and internalizing problems to be stronger for Han adolescents compared to ethnic minority adolescents.Psychological capital mediated the relationship between mindfulness and internalizing problems in both groups,with a negative direction.Findings support the Conservation of Resources theory and highlight mindfulness as a personal resource fostering adolescent well-being in multicultural contexts.
文摘Generalised reduced masses with a set of equations governing the three relative motions between two of 3-bodies in their gravitational field are established,of which the dynamic characteristics of 3-body dynamics,fundamental bases of this paper,are revealed.Based on these findings,an equivalent system is developed,which is a 2-body system with its total mass,constant angular momentum,kinetic and potential energies same as the total ones of three relative motions,so that it can be solved using the well-known theory of the 2-body system.From the solution of an equivalent system with the revealed characteristics of three relative motions,the general theoretical solutions of the 3-body system are obtained in the curve-integration forms along the orbits in the imaged radial motion space.The possible periodical orbits with generalised Kepler’s law are presented.Following the description and mathematical demonstrations of the proposed methods,the examples including Euler’s/Lagrange’s problems,and a reported numerical one are solved to validate the proposed methods.The methods derived from the 3-body system are extended to N-body problems.
文摘The proliferation of carrier aircraft and the integration of unmanned aerial vehicles(UAVs)on aircraft carriers present new challenges to the automation of launch and recovery operations.This paper investigates a collaborative scheduling problem inherent to the operational processes of carrier aircraft,where launch and recovery tasks are conducted concurrently on the flight deck.The objective is to minimize the cumulative weighted waiting time in the air for recovering aircraft and the cumulative weighted delay time for launching aircraft.To tackle this challenge,a multiple population self-adaptive differential evolution(MPSADE)algorithm is proposed.This method features a self-adaptive parameter updating mechanism that is contingent upon population diversity,an asynchronous updating scheme,an individual migration operator,and a global crossover mechanism.Additionally,comprehensive experiments are conducted to validate the effectiveness of the proposed model and algorithm.Ultimately,a comparative analysis with existing operation modes confirms the enhanced efficiency of the collaborative operation mode.
基金Supported by the Natural Science Foundation of Guangxi Province(Grant Nos.2023GXNSFAA026067,2024GXN SFAA010521)the National Natural Science Foundation of China(Nos.12361079,12201149,12261026).
文摘Convex feasibility problems are widely used in image reconstruction, sparse signal recovery, and other areas. This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery. We first derive the projection formulas for a vector onto the feasible sets. The centralized circumcentered-reflection method is designed to solve the convex feasibility problem. Some numerical experiments demonstrate the feasibility and effectiveness of the proposed algorithm, showing superior performance compared to conventional alternating projection methods.
基金supported by the National Natural Sci‐ence Foundation of China(Grant No.62306325)。
文摘During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive distance)to a moving target as quickly as possible,resulting in the extended minimum-time intercept problem(EMTIP).Existing research has primarily focused on the zero-distance intercept problem,MTIP,establishing the necessary or sufficient conditions for MTIP optimality,and utilizing analytic algorithms,such as root-finding algorithms,to calculate the optimal solutions.However,these approaches depend heavily on the properties of the analytic algorithm,making them inapplicable when problem settings change,such as in the case of a positive effective range or complicated target motions outside uniform rectilinear motion.In this study,an approach employing a high-accuracy and quality-guaranteed mixed-integer piecewise-linear program(QG-PWL)is proposed for the EMTIP.This program can accommodate different effective interception ranges and complicated target motions(variable velocity or complicated trajectories).The high accuracy and quality guarantees of QG-PWL originate from elegant strategies such as piecewise linearization and other developed operation strategies.The approximate error in the intercept path length is proved to be bounded to h^(2)/(4√2),where h is the piecewise length.
基金funded by National Natural Science Foundation of China(Nos.12402142,11832013 and 11572134)Natural Science Foundation of Hubei Province(No.2024AFB235)+1 种基金Hubei Provincial Department of Education Science and Technology Research Project(No.Q20221714)the Opening Foundation of Hubei Key Laboratory of Digital Textile Equipment(Nos.DTL2023019 and DTL2022012).
文摘Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems.
文摘The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet dynamics,are demonstrated in the current research.Hereby,the 2nd Stokes problem assumes that the surface,with a thin shared layer of the fluid on it,oscillates in a harmonic manner along the x-axis of the rivulet flow,which coincides with the main flow direction streaming down the underlying surface.We obtain the exact extension of the rivulet flow family,clarifying the structure of the pressure field,which fully absorbs the arising perturbation.The profile of the velocity field is assumed to be Gaussian-type with a non-zero level of plasticity.Hence,the absolutely non-Newtonian case of the viscoplastic flow solution,which satisfies the motion and continuity equations,is considered(with particular cases of exact solutions for pressure).The perturbed governing equations of motion for rivulet flows then result in the Riccati-type ordinary differential equation(ODE),describing the dynamics of the coordinate x(t).The approximated schematic dynamics are presented in graphical plots.
基金partly supported by the Beijing Natural Science Foundation(Grant No.Z200003)by the National Natural Science Foundation of China(Grant Nos.12331015,12301475,12301465)+1 种基金by the National Center for Mathematics and Interdisciplinary Science,Chinese Academy of Sciencesby the Research Foundation for the Beijing University of Technology New Faculty(Grant No.006000514122516).
文摘This study proposes a class of augmented subspace schemes for the weak Galerkin(WG)finite element method used to solve eigenvalue problems.The augmented subspace is built with the conforming linear finite element space defined on the coarse mesh and the eigen-function approximations in the WG finite element space defined on the fine mesh.Based on this augmented subspace,solving the eigenvalue problem in the fine WG finite element space can be reduced to the solution of the linear boundary value problem in the same WG finite element space and a low dimensional eigenvalue problem in the augmented sub-space.The proposed augmented subspace techniques have the second order convergence rate with respect to the coarse mesh size,as demonstrated by the accompanying error esti-mates.Finally,a few numerical examples are provided to validate the proposed numerical techniques.
文摘Intensive curing barn is an important component of flue-cured tobacco pro-duction in China, with progress made. However, problems stil exist, such as lower heat energy utilization efficiency and slow equipment update. In the research, opti-mization ways of tobacco barn were analyzed in flue-cured tobacco production re-gions, and assessment was made on improvement effects, in order to provide refer-ences for highly-efficient and low-carbon development of curing barn.
基金Supported by the Teaching Reform and Management Program of Shanghai Maritime University
文摘China is a large agricultural country. Healthy and rapid development of agriculture plays an important role in overall socialist construction of China. To realize sustainable agricultural development,cultivation of agricultural science and technology innovation talents should be strengthened. Through analyzing existing problems in cultivation of agricultural science and technology innovation talents and combining actual situation of China's agricultural development,this paper came up with pertinent recommendations for strengthening China's agricultural science and technology talent cultivation,including improving agricultural science and technology innovation talent cultivation system,implementing " government- industry- university- institute" talent cultivation mode,speeding up construction of experimental teaching demonstration center,and applying human resource theories.
基金Supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2007BAD89B18-03)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2012BAD14B14-01)
文摘In 2012,China's total grain yield reached 590 million tons and realized nine consecutive years of growth. This is huge historic achievement of China and also rare in development history of world agriculture. However,at the same time of making great achievements,China's agriculture is still confronted with many problems. On the basis of extensive survey,it pointed out 10 outstanding problems: farmland,labor,livestock power,water conservancy,input,agricultural disaster,ecological and environmental problem,waste of resources,economic scale and economic benefits. These problems have brought great adverse influence on China's agricultural development. In view of these problems,to realize sustainable,stable and healthy development of agriculture in the new period,it came up with following recommendations:( i)deepening the understanding;( ii) enforcing laws strictly;( iii) enhancing training;( iv) increasing benefits;( v) saving resources;( vi) protecting environment;( vii) developing science and technology;( viii) consolidating foundation.
文摘Since the seventies,world economy has been engaged in adjustment princi-pally in the following three fields.First,the shift of economic developmentmode from that of aggregate quantitative growth to that of quality-effective-ness.Second,the reform of economic system with more and more countries realiz-ing market economy.Third,the economy getting more opened as economic global-ization further avdances.
文摘The cultivation of the economic crop flue-cured tobacco is greatly impacted by natural climates,making it a risk industry.In recent years,flue-cured tobacco production is influenced by extreme weather such as typhoon,low temperature,hail,frost,drought,plant diseases and insect pests.It is imperative to establish a sound insurance system for tobacco planting.In this paper,the practice and functions of tobacco planting insurance in Qianxinan Prefecture were summarized,the experience and existing problems in the practice process were analyzed,and finally the countermeasures and suggestions were proposed to further improve the tobacco planting insurance.
基金The research has been financed by The Philosophy and Social Science Research Project in 2019 of Jiangsu Provincial Department of Education“Research on the Optimization of Scenic Spot Tourism signage system on the Background of Global Tourism”(Number:2019SJA1428).
文摘China takes the road of tourism development,and the tourism industry is gradually branded,which is also a reflect of tourism management to adapt to the trend of the times.Tourism is an important economic project for the participation of the whole people.By optimizing the local resources,the tourism space is carried out in an orderly manner,and the rich tourism products are displayed in front of the tourists.With the development of tourism,the scientific tourism system has been established,and the globalization of tourism has been realized.To promote the healthy development of tourism,tourist signs are essential.From the current established tourism signage system,there are still some problems,which affect the quality of tourism management.It is necessary to take corresponding countermeasures.This paper focuses on the causes and strategies in response to the existing problems in the tourism signage system.
文摘The development of rural industries in Bijie City of Guizhou Province leads the comprehensive rural revitalization with industrial revitalization,takes high-quality development as the overall guide,focuses on industrial scale,standardization,branding,and marketization,and strives to extend the industrial chain and enhance the value chain to achieve the prosperity of rural industries.In this study,it investigated the current situation of rural industry development in Bijie City(improving the quality and efficiency of characteristic industries,expanding the quantity and efficiency of agricultural products processing industry,recruiting and cultivating large business entities,expanding and strengthening the brand of agricultural products,and upgrading the rural tourism).Through analysis,it found that there are problems such as small scale of production enterprises,insufficient cultivation of independent brands,short industrial chain,low added value,weak market expansion ability,imperfect interest connection mechanism,and insufficient participation of farmers.Finally,it came up with countermeasures for the development of rural industries in Bijie City,including improving supporting facilities and building an extension base;strengthening leading enterprises and focus on deep processing;highlighting regional characteristics and paying close attention to the docking of production and marketing;enhancing the characteristic brand and strengthening the support of science and technology;promoting collaboration and support,and making innovation in the connection of interests.
文摘In this paper,status quo of water pollution control in the Longgang River Basin is summarized,and the current status of water environment quality is analyzed,and the main problems in water environment management are discussed.The research aims to provide reference for the management of the Longgang River basin.
文摘Performance management is one of the important contents of enterprise operation management. The effectiveness of performance management will directly affect the overall performance of the enterprise, so the development of performance management is of great significance. But from the current situation, there are still some deficiencies in the performance management of many enterprises, leading to the actual role of performance management can not be played. Therefore, we should analyze and optimize the existing problems of enterprise performance management system.
文摘At present, China's social and economic development is accelerating, and the quality and overall level of municipal road projects have been greatly improved. However, with the prosperity of traffic, road traffic congestion and road aging problems have become increasingly prominent. The renovation project of old municipal roads has gradually become the focus of attention. The transformation of municipal roads is imminent. Therefore, we must strictly control the construction quality of the old road renovation project municipal roads, ensure the control and measurement of the old road renovation project municipal roads, and then improve the overall environmental level of the city, increase the residents' sense of belonging, and promote the rapid development of the urbanization process .